Recherche avancée

Sur d’autres sites (11814)

• Syncing decoded video using Ffmpeg

  30 juin 2012, par Infiniti Fizz

  I am using Ffmpeg to decode and play video files. I have currently got the video playing and the audio playing at as fast as the CPU can decode and display them. The problem is that I want to play the video and audio in sync using the system clock.

  I've searched around for some help but can't find anything substantial other than dranger's tutorial 05 but I don't really understand what he is doing because my program isn't written in the same way as his.

  I am using mjpeg files and so the pts seems to be retrieved every single time a frame is decoded, I have multiplied the pts by the time_base as dranger does to get the value in seconds but the resolution seems to be only seconds and so I get the value "6" 25 times and then "7" 25 times as the video runs at 25 frames per second.

  Is there not a more accurate value ? Or way to get a more accurate value and if so, how would I go about syncing to this value ? I am using SDL to display the value so can I just use a SDL_Delay() of the value I get ?

  Thanks for your time,

  Infinitifizz

• FFmpeg per stream metadata change with more audio streams

  22 août 2014, par tomasb

  I’m trying to change audio stream title for a movie which was originally with DTS sound. I have added AC3 version using -map parameter, want to keep both. My problem is that the AC3 audio stream bears DTS stream metadata. I am using FFmpeg 1.2

  Tried :

  ffmpeg -i movie.mkv -c copy \
  
  -metadata:s:1 title="AC3 5.1 640 kb/s" -y movie.temp.mkv 

  this partially works, but output file contains only 1 of each stream type, i.e. 1 video, 1 audio and 1 subtitle stream. When i try to get all the streams contained in my mkv like this :

  ffmpeg -i movie.mkv -map 0 \
  
  -metadata:s:1 title="AC3 5.1 640 kb/s" -y movie.temp.mkv 

  i am getting strange output :

  Stream mapping:
  
    Stream #0:0 -> #0:0 (h264 -> libx264)
  
    Stream #0:1 -> #0:1 (ac3 -> libvorbis)
  
    Stream #0:2 -> #0:2 (subrip -> ass)
  
    Stream #0:3 -> #0:3 (dca -> libvorbis)
  
    Stream #0:4 -> #0:4 (ac3 -> libvorbis)
  
    Stream #0:5 -> #0:5 (subrip -> ass)
  
  Press [q] to stop, [?] for help
  
  [libvorbis @ 0x12e5a40] Queue input is backward in time
  
      Last message repeated 19 times
  
  Queue input is backward in time      20kB time=00:00:01.05 bitrate= 156.8kbits/s    
  
  [libvorbis @ 0x12e5a40] Queue input is backward in time
  
      Last message repeated 17 times
  
  Queue input is backward in time      20kB time=00:00:01.99 bitrate=  83.0kbits/s    
  
  [libvorbis @ 0x12e5a40] Queue input is backward in time
  
      Last message repeated 5 times
  
  Queue input is backward in time=      20kB time=00:00:02.38 bitrate=  69.5kbits/s    
  
  [libvorbis @ 0x12e5a40] Queue input is backward in time
  
      Last message repeated 6 times
  
  Queue input is backward in time=      20kB time=00:00:02.87 bitrate=  57.5kbits/s    
  
  [libvorbis @ 0x12e5a40] Queue input is backward in time
  
  ...

  I have found information that FFmpeg’s attributes under linux are inconsistent when manipulating per stream metadata and doesn’t work as expected so I am looking for some alternative way how to proceed. (preferably with ffmpeg)

  Thanks for any help.

• Senior Software Engineer for Enterprise Analytics Platform

  28 janvier 2016, par Matthieu Aubry — Jobs

  We’re looking for a lead developer to work on Piwik Analytics core platform software. We have some exciting challenges to solve and need you !

  You’ll be working with both fellow employees and our open-source community. Piwik PRO staff lives in New Zealand, Europe (Poland, Germany) and in the U.S. We do the vast majority of our collaboration online.

  We are a small, flexible team, so when you come aboard, you will play an integral part in engineering. As a leader you’ll help us to prioritise work and grow our community. You’ll help to create a welcoming environment for new contributors and set an example with your development practices and communications skills. You will be working closely with our CTO to build a future for Piwik.

  Key Responsibilities

  • Strong competency coding in PHP and JavaScript.
  • Scaling existing backend system to handle ever increasing amounts of traffic and new product requirements.
  • Outstanding communication and collaboration skills.
  • Drive development and documentation of internal and external APIs (Piwik is an open platform).
  • Help make our development practices better and reduce friction from idea to deployment.
  • Mentor junior engineers and set the stage for personal growth.

  Minimum qualifications

  • 5+ years of experience in product development, security, usable interface design.
  • 5+ years experience building successful production software systems.
  • Strong competency in PHP5 and JavaScript application development.
  • Skill at writing tests and reviewing code.
  • Strong analytical skills.

  Location

  • Remote work position !
  • or you can join us in our office based in Wellington, New Zealand or in Wrocław, Poland.

  Benefits

  • Competitive salary.
  • Equity in Piwik PRO.
  • Remote work is possible.
  • Yearly meetup with the whole team abroad.
  • Be part of a successful open source company and community.
  • In our Wellington (NZ) and Wroclaw (PL) offices : snacks, coffee, nap room, Table football, Ping pong…
  • Regular events.
  • Great team of people.
  • Exciting projects.

  Learn more

  Learn more what it’s like to work on Piwik in our blog post

  About Piwik

  At Piwik and Piwik PRO we develop the leading open source web analytics platform, used by more than one million websites worldwide. Our vision is to help the world liberate their analytics data by building the best open alternative to Google Analytics.

  The Piwik platform collects, stores and processes a lot of information : hundreds of millions of data points each month. We create intuitive, simple and beautiful reports that delight our users.

  About Piwik PRO company

  At Piwik PRO we’re solving hard problems with simple solutions that make our users and customers happy. We practise agile methodology, test driven development and fast release cycles. Our backend is mostly built in modern PHP with a bit of Python. We use MySQL/MariaDB and Redis as data stores. Our frontends is built in JavaScript using AngularJS and jQuery. Our tools include Github, Travis CI, PhpStorm and Slack.

  As a Lead Software Developer for Piwik PRO, you will be writing open source code that will run on more than 200,000 servers and be used in 200+ countries and 50 languages !

  Apply online

  To apply for this position, please Apply online here. We look forward to receiving your applications !